This invention relates to a system for portioning material, such as ground meat, as the material is being conveyed at a substantially constant rate of speed, and for thereafter depositing the portioned material on a tray or the like.
In the past, a labor-intensive and relatively inaccurate manual operation has been employed to portion material, such as ground meat, as the material is conveyed on a conveyor belt or the like. The ground meat is output onto the conveyor belt in a ribbon or strand having a substantially constant cross-section, and thereby a controlled density. The strand of meat is manually cut to a predetermined length with the assistance of evenly spaced markings on the conveyor belt, thereby providing a portion having a predetermined weight according to its length. The portion is then placed onto a tray and wrapped.
The present invention provides an automatic system for providing a portion of material, such as ground meat, having a predetermined weight according to its length, and for automatically depositing the individual meat portions onto a tray.
In accordance with one aspect of the invention, a mechanism for portioning material includes material supply means for depositing a strand of material onto conveying means for moving the material in a first direction. Portioning means is provided for intermittently separating the material at predetermined intervals. The conveying means uninterruptably moves the material in the first direction at a substantially constant rate of speed, and the portioning means intermittently separates the material as it is being moved in the first direction by the conveying means. In this manner, portioning of the material can be accomplished without interruption of the conveying means. In a preferred embodiment, the portioning means comprises carriage means selectively movable in the first direction at the same rate of speed as the conveying means. Selectively actuable knife means is mounted to the carriage means, and the knife means acts to separate the material when the carriage means is moving in the first direction. The carriage means is preferably reciprocably movable between a first position and a second position, alternately moving in the first direction and in a second direction opposite thereto between the first and second positions. The conveying means is preferably a belt conveyor, and the knife means provides a downward cutting stroke for severing the material against the conveyor belt. Thereafter, the knife means undergoes an upward return stroke during movement of the carriage means in the second direction, for readying the knife for another downward cutting stroke. Reciprocating movement of the carriage means is preferably provided by a reciprocating mechanism including means traveling in the first direction at the same rate of speed as the conveying means; means traveling in the second direction, and means interconnected with the carriage means for alternately selectively coupling the carriage means with the first direction traveling means and the second direction traveling means, respectively. In a preferred embodiment, the means traveling in the first direction and the means traveling in the second direction comprise a timing belt providing an upper run and a lower run, one of which travels in the first direction and the other of which travels in the second direction. The means interconnected with the carriage means selectively couples the carriage means to the upper and lower runs of the timing belt for alternately moving the carriage means in the first and second directions. The timing belt is preferably driven by the same drive mechanism as the conveying means so as to ensure that the run of the timing belt traveling in the first direction travels at the same rate of speed as the conveyor. First and second clutches are preferably interconnected with the carriage means for selectively engaging the first direction traveling means and the second direction traveling means, respectively. With the timing belt system mentioned previously, the first and second clutches are preferably mounted to a shuttle which provides passages for the upper and lower runs of the timing belt. The first and second clutches preferably comprise selectively actuable clutch plates mounted to the piston rods of clutch cylinders, for alternately coupling and decoupling the shuttle to and from the upper and lower runs of the timing belt. In this manner, reciprocating movement of the carriage is provided. An actuating system is employed for controlling actuation of the first and second clutches, and thereby their engagement with the timing belt, and also for controlling movement of the knife. The actuating system is preferably pneumatically operated, and includes selectively placed air actuator valves for controlling movement of the clutches and the knife.
In accordance with another aspect of the invention, a mechanism for depositing an article, such as a tray, by gravity onto a surface, such as a tray supply conveyor, comprises a receptacle adapted to receive a stack of articles. Dispensing means is disposed toward the lower end of the receptacle for depositing the articles one by one onto a surface therebelow from the bottom of the stack of articles. The dispensing means deposits the articles by allowing the lowermost article to fall onto the surface while supporting the articles in the stack above the lowermost article. In a preferred embodiment, the dispensing means comprises first movable stack support means movable into and out of engagement with the lowermost article in the stack, and second movable stack support means movable into and out of engagment with the tray above the lowermost tray in the stack. When the first stack support means is engaged with the lowermost article for supporting it along with the remainder of the stack, the second stack support means is out of engagement with the stack. Upon movement of the second stack support means into engagement with the article above the lowermost article, for supporting it along with the remainder of the stack, the first stack support means is moved out of engagement with the lowermost article, thus releasing it to fall onto the surface. Both the first and second stack support means preferably comprise spaced pairs of movable members such as support plates, with the stack of articles disposed therebetween. The support plates are preferably mounted in horizontal slots formed in a pair of spaced support blocks, and actuator means controls the retraction or extension of the plate members in a predetermined sequence. The actuator means preferably comprises a vertically movable actuator plate having cam slots formed therein, with the horizontally movable support plates having cam followers mounted in the cam slots for controlling extension and retraction thereof. A pivotable tray kicker is preferably provided for assisting in forcing the lowermost tray downwardly onto the lower surface.
In accordance with yet another aspect of the invention, the portioning system and the tray dispenser are incorporated into a single apparatus in which the trays are supplied to the portioning apparatus in a manner so that the portions of material are deposited onto the trays upon discharge from the material conveyor.